1. Field of the Invention
The invention is related to the field of fuel dispensing and, more particularly, to a fuel dispensing system suitable for controlling, authorizing and accounting for liquid dispensed from liquid petroleum fuel dispensers without requiring control and authorization input from individuals performing the fueling.
2. History of the Related Art
Solid state microcontroller-based fuel control and accounting systems have been commercially available since the early 1980s. The known systems have incorporated many methods of accessing and transferring authorization data, including read-only electronic keys, read/write electronic keys, keypad entry, read-only radio frequency ("RF") identification ("ID") tags, read/write RF/ID tags, magnetic stripe cards, bar code readers and inductive coil antennae. Systems providing these means of data access are presently available from a large number of commercial companies.
Each of the known systems has disadvantages. The one common disadvantage of most of the systems is the inability to automatically positively identify the vehicle being fueled. In that the systems require some operator input, the operator input can produce fuel control and accounting errors. Although the known systems have reduced the chance of operator error, each has generated a major disadvantage in the process. The inductive coil antennae pair reduces possible operator errors; however, this system requires a communication wire be affixed to the fueling hose so that communications can be accomplished via an inductive coil antennae pair mounted on the fuel nozzle and on the vehicle's filler neck.
Two types of RF/ID tags exist: short-range and long-range varieties. Short-range RF/ID Tags have very short-range operational characteristics that assure that only one RF/ID Tag responds to a reader's interrogation. However, when long-range RF/ID Tags are used for fueling, all RF/ID Tags within range of a reader respond to that reader's interrogation. This response characteristic dictates that a secondary source of information is required in order to ascertain with which vehicle the long-range RF/ID Tags is associated. This operational characteristic presents a major problem for RF/ID Tag associated fueling scenarios.
U.S. Pat. No. 4,253,945 to Van Ness discloses an automatic control system for dispensing fuel to vehicles. The system comprises a fuel control transmitter attached to a vehicle and a receiver unit attached to a fuel dispenser. This system provides no positive assurance that the dispenser's fuel nozzle is actually installed in the vehicle to which the fuel control transmitter is affixed. Also, no memory is provided in the receiver units, requiring each receiver unit to be on-line with a computer configured with logic and memory capabilities. Further, a receiver unit must be attached to each dispenser and each receiver must be on-line with the computer.
U.S. Pat. No. 5,204,819 to Ryan discloses an apparatus for authorizing the delivery of fuel to a vehicle from a fuel delivery device. The apparatus comprises an unpowered RF/ID tag associated with a vehicle, and a second device associated with the fuel delivery device which reads the RF/ID tag, authorizes and controls fuel delivery. This system's unpowered RF/ID tag lacks the capability to directly monitor and accrue the vehicle's mileage. In order to monitor and accrue the vehicle's mileage, the vehicle would require an on-board computer configured for these tasks, and for transfer of the accrued vehicle's mileage to the unpowered RF/ID tag for subsequent transfer to the second device. The second device's location on the fuel nozzle requires recharging of the second device's batteries, and/or electrical wires running along/or in the fuel hose for a supply of the recharge power. The second device would be required to control the flow of fuel through direct valving in the nozzle, to monitor the quantity of fuel dispensed through a pulser mounted in the fuel nozzle, and to be intrinsically safe in accordance with requirements as defined by ANSI/UL 913 (for example, current limited and extremely low power). For the second device to be capable of RF communications with a remote location, further power would be required from this second device and this further burdens the technical feasibility of meeting the intrinsic safety driven power limitations of the second device.
U.S. Pat. No. 5,359,522 to Ryan discloses an apparatus for two-way communications between a vehicle and a fuel delivery device. The apparatus comprises a first two-way communications device associated with a fuel delivery device, and a second two-way communications device associated with a vehicle. This apparatus has increased communicative abilities between the vehicle associated device and the fuel delivery associated device relative to the system of U.S. Pat. No. 5,204,819. The device locations on the fuel nozzle and on the vehicle are as disclosed in U.S. Pat. No. 5,204,819. However, the increased communicative disclosures further burden the technical feasibility of meeting intrinsic safety driven power limitations relative to the safety requirements as defined by ANSI/UL 913.
Thus, there is a need for a system which, when integrated into the multiplicity of technical data transfer requirements, eliminates the need for operator input and, accordingly, eliminates operator error.